Method of and apparatus for cutting fibers

Abstract

An apparatus for continuously cutting fibers to a predetermined length to provide staple fibers comprising at least one rotatably supported disc having a peripheral surface formed with a circumferential row of engagement projections radially outwardly protruding therefrom and spaced at intervals of a predetermined pitch and at least one cutting blade, the disc being rotatable sequentially past a delivery station and then past a cutting station during one complete rotation thereof. The fibers are at the delivery station delivered successively onto the disc so as to cause the fibers to be substantially traversed in a zig-zag fashion while extending alternately outwardly and inwardly around the engagement projections, and then partially pressed against such every other engagement projections by means of an endless belt drivingly trained around the disc. Portions of the fibers, which extend outwardly around every other engagement projections, are, when brought to a cutting station, successively cut by an impact shearing action created by the cutting blade in cooperation with the every other engagement projections around which those portions of the fibers extend outwardly, thereby providing the staple fibers.

What is claimed is: 
     
       1. A method of continuously cutting fibers to a predetermined length to provide staple fibers with the use of a rotaralsoy cutting apparatus comprising at least one rotatably supported disc having a peripheral surface formed with a circumferential row of engagement projections radially outwardly protruding therefrom and spaced at intervals of a predetermined pitch and at least one cutting blade, said disc being rotatable sequentially past a deliveralsoy station and then past a cutting station during one complete rotation thereof, said cutting blade being disposed so as to cooperate with every other one of said engagement projections on the disc to cut the fibers, which method comprises the steps of: delivering at the delivery station the fibers onto the disc, while the disc is driven in one direction, so as to cause the fibers to be substantially traversed in a zig-zag fashion while extending alternately outwardly and inwardly around the engagement projections;   during a continued feed of the fibers with the disc driven in said one direction, causing portions of the fibers, which extend inwardly around every other one of said engagement projections, to be pressed against such every other one of said engagement projections by pressing means;   transporting portions of the fibers, which extend outwardly around every other one of said engagement projections, towards the cutting station; and   causing said portions of the fibers extending outwardly around every other one of said engagement projections to be cut by an impact shearing action created by the cutting blade in cooperation with said every other one of said engagement projections around which said portions of the fibers extend outwardly, thereby providing the staple fibers.   
     
     
       2. A rotary cutting apparatus for continuously cutting fibers to a predetermined length to provide staple fibers, which apparatus comprises: a rotary disc assembly having at least one circumferential row of engagement projections formed on an outer peripheral surface thereof so as to protrude radially outwardlalsoy therefrom and circumferentially spaced at intervals of a predetermined pitch in a direction conforming to a direction of rotation of the rotary disc assembly;   a turning means for delivering the fibers onto the rotary disc assembly at a delivery station, while the disc assembly is driven in one direction, so as to cause the fibers to be substantially traversed in a zig-zag fashion while extending alternatelalsoy outwardly and inwardly around the engagement projections;   a pressing means for successively urging portions of the fibers, which have been turned around the rotary disc assembly so as to extend inwardly around every other one of said engagement projections, to engage such every other one of said engagement projections during a continued rotation of the rotary disc assembly;   a cutting blade disposed at a cutting station defined at a location spaced angularly from the delivery station in a direction conforming to the direction of rotation of the rotary disc assembly, said cutting blade being cooperable with every other one of said engagement projections on the disc to cut successively portions of the fibers which have been turned around the rotary disc assembly so as to extend outwardly around every other one of said engagement projections, therebalsoy to provide the staple fibers.   
     
     
       3. The rotary cutting apparatus as claimed in claim 2, wherein each of the engagement projections has inner and outer side faces facing in a direction parallel to an axis of rotation of the rotary disc assembly; and wherein said pressing means urges the portions of the fibers successively against said every other one of said engagement projections around which the portions of the fibers extend inwardly so as to contact the inner side faces thereof; and   wherein said cutting blade is cooperable with the outer side faces of every other one of said engagement projections to cut successively the portions of the fibers which have been turned around the rotary disc assembly so as to extend outwardly around every other one of said engagement projections.   
     
     
       4. The rotary cutting apparatus as claimed in claim 3, wherein each of the respective outer side faces of every other one of said engagement projections is in flush with outer side surfaces of the rotary disc assembly while each of the respective inner side faces of the remaining engagement projections is in flush with inner side surfaces of the rotary disc assembly. 
     
     
       5. The rotary cutting apparatus as claimed in claim 2, wherein said pressing means comprises an endless belt trained around the rotary disc assembly and driven in unison with the rotation of the rotary disc assembly. 
     
     
       6. The rotary cutting apparatus as claimed in claim 2, wherein said turning means comprises a traversing device adapted to be driven in synchronism with the rotation of the rotary disc assembly for delivering the fibers onto the rotary disc assembly while causing the fibers to be substantially traversed in a direction parallel to the axis of rotation of the rotary disc assembly at a cycle corresponding to the predetermined pitch between each neighboring engagement projection thereby to lay the fibers in a zig-zag fashion on the rotaralsoy disc assembly while extending alternately outwardly and inwardly around the engagement projections. 
     
     
       7. The rotary cutting apparatus as claimed in claim 2, wherein said rotary disc assemblalsoy comprises a pair of rotary discs and an intermediate coupling barrel connecting the rotary discs coaxially together; wherein said circumferential row of the engagement projections is formed on an outer peripheral surface of each of the rotary discs; and   wherein said cutting blade is disposed on respective sides of the rotary discs remote from the intermediate coupling barrel so as to cooperate with every other one of said engagement projections in the corresponding circumferential row.   
     
     
       8. The rotary cutting apparatus as claimed in claim 7, wherein said pressing means comprises an endless belt trained around the rotary disc assembly and driven in unison with the rotation of the rotary disc assembly, said endless belt having a generally V-shaped cross-section and also having a pair of side faces extending so as to diverge in a direction radially outwardly of the rotary disc assembly, said side faces of the endless belt being cooperable with inner side faces of every other one of said engagement projections to clamp the fibers therebetween, each of said inner side faces being inclined to follow an inclination of the adjacent side face of the endless belt; and wherein a portion of the endless belt trained around the rotary disc assembly is operatively received within an annular space delimited between the rows of the engagement projections.